$ sudo apt-get remove festlex-cmu 

Uninstall festlex-cmu including dependent package

If you would like to remove festlex-cmu and it's dependent packages which are no longer needed from Ubuntu,

$ sudo apt-get remove --auto-remove festlex-cmu 

Use Purging festlex-cmu

If you use with purge options to festlex-cmu package all the configuration and dependent packages will be removed.

$ sudo apt-get purge festlex-cmu 

If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.

$ sudo apt-get purge --auto-remove festlex-cmu 

See Also,